1. Field of the Invention
The present invention relates generally to apparatus for facilitating the movement of a plunger of a syringe through a barrel of the syringe and, more particularly, to hand-held, hand operated apparatus that facilitate the movement of a plunger through a syringe barrel. More specifically, the present invention relates to hand-held apparatus with scissor grip type leveraged triggering systems that force a plunger of a syringe through the length of the barrel of the syringe.
2. Background of Related Art
The use of syringes for aspirating biological samples from the bodies of subjects is well known. Typically, the barrel of a syringe is placed in communication with a desired location of a subject's body, then a vacuum is created within the barrel of a syringe by pulling a plunger of the syringe toward a proximal end of the syringe (i.e., toward the syringe user, away from the body of the subject). When a vacuum is formed within the barrel of a syringe, fluid from the desired location is drawn into the syringe.
This process can be very difficult with existing devices, as syringes that are configured to reduce a user's exertion are also typically configured for fluid delivery rather than for aspiration. For example, in many conventionally configured syringes, aspiration is effected by holding the barrel of the syringe with one hand while pulling the plunger with another hand. Similar actions must be taken when many other types of manually operated devices are used to facilitate aspiration with a syringe.
There are needs for syringes that are configured to be held, or suspended, and operated by the same hand of a user and that may be comfortably operated.